Power line communication (PLC), also called mains communication, power line transmission (PLT), broadband power line (BPL), power band or power line networking (PLN), is a term describing a method for using power distribution wires for simultaneous distribution of data. A carrier can communicate voice and data by superimposing an analogue signal over the standard 50 Hz or 60 Hz alternating current (AC). For indoor applications PLC equipment can use household electrical power wiring as a transmission medium.
However, power line communication between devices within a power line communication system may be interfered by other devices or systems outside the power line communication system but connected to the same electrical power wiring, e.g. vacuum cleaner, electric drill or switching power supplies, by other external sources, e.g. other PLC systems, by disturbances in the mains power network or by other noise sources.
Therefore, other carriers for distributing data are used for short distances between devices communicating with each other, for instance HDMI cable. This may result in a plurality of cables connecting different communicating devices with each other or in a complicated network architecture.
It is an object of the invention to enable a power line communication between a plurality of devices of a power line communication system without interferences from outside the power line communication system. Another object of this invention is to provide a power line communication system, which does not interfere with other devices or systems connected to the mains anywhere in the building. These other devices or systems might be radio receivers, other PLC systems, etc.
The objects are solved by a device according to claim 1, by power line communication systems according to claims 7 and 12, respectively, and by a power line communication method according to claim 15.
Further embodiments are defined in the dependent claims.
Further details of the invention will become apparent from a consideration of the drawings and ensuing description.